Mixing apparatus



Jam 8, 1953 i K. A. ANDERSON 3,072,462

' MIXING APPARATUS Filed Sept. l?, 1959 4 Sheets-Sheet 1 Ar in (-Alr InAir ln y Air-in -V Karl Allan Anderson BYE;

Ahorney K. A. ANDERSON MIXING APPARATUS Jan. 8, 1963 4 Sheets-Sheet 2IIB JNVENTOR;

Allan Anderson Karl Filed Sept. 17. 1959 IIB Attorney K. A. ANDERSONMIXING APPARATUS Jan. 8, 1963 4 Sheets-Sheet 3 Filed Sept. 17. 1959 Jan.8, 1963 K. A. ANDERSON 3,072,462

` MIXING APPARATUS Filed sept. 17, 1959 4 sheets-sheet 4 loo 75 IVN V ENTOR.

M Karl Allan Anderson United States Patent() 3,072,462 e MIXINGAPPARATUS Karl Allan Anderson, Park Ridge, Ill., assignor to ControlsCompany of America, Schiller Park, Ill., a corporation of Delaware Filedsept. 17, 1959, ser. No. s40,7z7` s claims. (ci. 23-252) This inventionrelates to mixing apparatus -and process particularly suited forhandling highly abrasive and adhesive materials of a fast setting nature'but useable' wherever `accurate on stream mixing is desired.

`Compounds containing resin possess chemical and electricalcharacteristics which Iare desirable for sealing or encapsulatingelectrical components. Physically, the resin is an extremely `adhesivematerial, and Vthe addition of 'fillers to the resin to lower theshrinkage rate and to increase economy introduces -an extremely abrasivecharacteristic to the material which presents problems in handling. Byproper selection and proportioning of resin and filler together withproper addition of a catalyst (hardener) the cure time can be broughtdown to a matter of fminutes (assuming the resin, iiller and hardener-are hot when mixed). This aggravates the problem of handling since wenow have an extremely ladhesive and abrasive material which must beaccurately and completely mixed and poured into the -mold quickly sothat it will not set in `the .handling equipment. VThis necessitates anon-stream `type ofmixing operation in which the lled resin(hereinafterreferred to as resin) `and the hardener-are inter--mittently fed simultaneously atta proportioned rate to -a mixer whichWill instantly mix the hardener and resin V,and purge itself completelyof the mixed material so that it will not set within the mixer. v

Due to the abrasive nature of the products involved,

-the most practical pump to ibe utilized to meterthe material is apositive displacement diaphragm pump which mustlbeserviced periodically.The ller, for example,

`maytend .to settle out of the mix within the pump during shut `downcreating obstructions to the normal flow of Vmaterial through the pump.Pumps of this type general- ;ly require that `the seal at the diaphragmbe broken to service the interior of the pump. This is undesirable sincerbreaking the seal introduces the possibilityof lcreatingl leaks in thehydraulic system and further requires that -the hydraulic system bedrained when only Vthe metering portion of the-pump needs to beserviced.It is therefore `an object ofthis invention toprovide adiaphragm pumpwhich can be opened for servicing without disturbing the seal .at thediaphragm.

In `order to insure that the vresin and hardener beheld a minimum amountof time yafter mixing, it is desirable i to provide on-stream mixing ofthe materials. I The specie mixer employed 'in the present inventionisthe subject matter vof a separate application Serial Number 841,135,

filed September V21, 1959.

Sinceon-stream-mixingis desired, is necessaryto provide a positivesystem for simultaneously a'ctuatmg the Y resin and hardener pumps .atproportionate rates toV insure FIGURE 1 is a schematic view of thel:apparatusused for metering and mixing them resin and'hardener.

3,072,462 Patented Jan. 8, 1 963 FIGURE 3 is taken on line 3---3` ofFIGURE 2 showing .the cam arrangement for the proportioning device.

'FIGURE 4 is an end view of the pump.

FIGURE 5 is .taken on line 5-5 of FIGURE 4 showing -a sectional viewofthe hydraulic pump system.`

FIGURE 6 `is a vertical section of the diaphragm pump.

In the mass production type of operation contemplated herein, the objectlto be encapsulated is placed in -a mold. The metering and dispensingsystem deliver a measured quantity of therencapsulating material to thelmold, which material must contain a proper proportion of the resin andhardener to obtain the desired cure time. Where a very short cure timeis desired, it becomes highly important to mix the resinan-d thehardener immediately before use and only in such quantity as -will beused in a `single shot to the mold. The present mixer is designed toreceive larproportional amountof resin and hardener continuously `fromthe metering pumps, mix it on-stream `and immediatelydispense it to themold containing the `productto be encapsulated. n

As seen in FIGUREl, resin and hardener are supplied from pressurizedreservoirs -10 land 12, respectively, to metering Vpumps 14,14 whichcontrol the volume of .resin and hardener supplied .to the mixer 16..'Pumps.14, 14 are actuated Iby a proportioning device 18 throughhydraulic rams 20, 20 sothat `a proportional Volume of resin andhardener is supplied at uniform rates to .the mixer throughout theentire actuating motion of the proportioning device. The mixer outletcommunicates With bell 2.2 which is evacuated during injection lby pump24 lthrough. check valve 26.

The resin and hardener `are de-aerated and stored in Ereservoirs 10 and12. These reservoirs are kept under a constantpressure to insure a readysupply to the metering pumps 14, 1:4. lBecause thefeed systems for theresin and hardener are identical, theoperation of thehardener -sys- 4temonly 'will be explained hereinafter.Y The metering .pumpis divided intotwo chambers 28 and '30 by da- .phragmz sealed to front vplate 34 bydiaphragm ring k36. Hardener is admitted to chamber 30 throughpassage 38in -back plate d0-:and controlled by air yactuated diaphragm type valve44 positioned at the inlettothe passage. ,By increasing the `airpressurebehind valve 144 to a .pressure higher than that of the hardener supplythe diaphragm will seat on sleeve 46 so that the *flow of hardener ,tothe ,passage vis cut off when chamber 30 `has Ibeen rilled.`V 1Asimil-artype valve 52.is used to control theoutlet passage 48 fromcharnber.'30. When chamber 30 has ,been.iille d, the diaphragm 'isactuated Iby ,increasing the vpressure in chamber 28 A'(to be describedhereinafter) and frelieving thefpressure `on theoutlet valve so that the.diaphragm forces thejhardenerfrom chamber 30. Ihe maxilimit ofmovementof the diaphragmis. determined byadiaphragm seat 56.seoured between thebackV plate ,and fthe ydiaphragm ring toprevent Vexcessive stretching:and-possiblelgupture of the diaphragm. The diaphragm seatis providedwith apluralityrof orriceslltlwl to allow .the free dow of hardenerthroughthe chamber. "At the .endof -themovement orf-the diaphragm,outlet valvexSZ closedand inlet Avalve'll is -opened allowing the'4pres- .surized hardener to refill the, chamberand force-the dia-Yphragmibaclcto its original position. e

. v'-"lheinletandoutletvalve assemblies 42', 50 are independent units ofsimilar construction. In 'the inlet as- 5sembly an air passage 62 isprovided in the coverplate FIGUR-E2. is a front elevation oftheproportionihg device.

58 and' is connected' to chamber 43; behind diaphragm t'ype valve 44;Control ofthe air pressure in chamber 43 `'will seat the diaphragm valveon sleeve 46. Resin and hardenerare stored intreservoirs lll-and 12which are connected 'to inlet' passages :.64 by iiexible tubes 11 and13,-respectively.f The resin andhardenerare forced under pressure pastvalve 44 through sleeve 46 and passage 38 into chamber 30 when the airpressure behind valve 44 is less than the pressure of the resin orhardener. Outlet valve assemblies 50 are similar to the inlet valveassembly, having diaphragm type valves S2 that are movable by airpressure into engagement with sleeves 54 and are connected to mixer 16by iiexible connections S3, 55. The valve assemblies are mounted on theback plate of the pump and held thereon by bars 66 fulcrumed on post 68and are forced against the valve assemblies by nuts 70 on studs 72. Thevalve assemblies are held in place by lthe bars 66 and sealed by O ringseals 74. The back plate is secured to the front plate by bolts 75angularly spaced about the outer periphery of the face of the back plateand passing through the diaphragm seat and the diaphragm ring. Thediaphragm ring is secured separately to the front plate by screws 27alternately spaced with respect to bolts 75. O ring seals 79 areprovided between the diaphragm ring and seat and between the diaphragmseat and the back plate to seal the metering chamber. With thisarrangement the back plate and diaphragm seat can be removed from thepump without breaking the seal of the diaphragm, in eiect making thehydraulic system independent, and without disturbing the seal on theflexible connection. The back plate and seat can then be cleaned and ifnecessary the inlet and outlet valves removed by releasing bars 66 fromstuds 72.

The metering pump is actuated by hydraulic system 20 which includescylinder 80 and piston l82 axially moveable therein. The cylinder has adiameter greater than the diameter of the piston. Hydraulic iluid flowsinto the cylinder through inlet valve 86 from supply reservoir 88. Airis bled through air bleed valve 90. The cylinder is connected to inletpassage 92 in the front plate of the pump through outlet 94 and passage96. The piston is moveable through Teflon rings 98 which seal the pistonwithin the cylinder and prevent uid leakage around the piston so thatthe full hydraulic force created within the reservoir on movement of thepiston is exerted on the diaphragm in the pump. When filling thecylinder in the ram with hydraulic fluid, the fluid is allowed to flowinto chamber 28 in the metering pump and air is bled therefrom throughair bleed valve 76. It is important to the operation of the system thatall the air be bled from the cylinder and chamber 28` when filled sothat the hydraulic system is incompressible.

The hydraulic rams for the metering pumps are controlled simultaneouslyby the motion of a pair of levers 102 connected at their lower ends tothe pistons of the rams and pivoted at their upper ends in pins 104projecting from stationary plate 106. The levers are moved back andforth by the action of cam followers 114 slide- Vably engaging grooves108 `provided in cam plates 110.

The cam plates are secured to front plate 1112 which is moved verticallyup and down by a double acting air cylinder 124. The cam plates arepivoted on pins 116 so that the angle of the groove with respect to'thelever can be varied by adjusting screws 118 and set by screws 120 inslots l122. The front plate is connected to crosshead 130 by spacer V126which is vertically moveable between guides 125 and held thereon byretainers i132'and to the air cylinder'by rod 128 connected to spacerr126.

the levers.

When the metering pumps are actuated, air pressure on the outlet valvesis relieved and the diaphragms force the resin and hardenersimultaneously out of the pumps "to the mixer. The amount of resin andhardener-metered vto the mixer depends on the speed and stroke of thepis- 'ltons in 'the hydraulic rams.` .The maximum movement of thediaphragms is limited by the diaphragm seat to prevent rupturing thediaphragm. At the end of the piston pumping stroke, the air outletvalves are closed and the air inlet Valves opened allowing thepressurized resin and hardener to flow into the pumps. The air cylinderis pressurized as the outlet valve is opened to slowly move the frontplate upward returning the levers to their initial position so that thediaphragms are moved back to their normal position by the pressure ofthe resin and hardener. By having the resin and hardener move thediaphragm back to its normal position, rather than the diaphragm beingpulled back by the hydraulic iluid and creating a Vacuum within thepumps, the possibility of air leaking into the pumps is eliminated.

In filling the device the resin and hardener supply chambers are keptunder a constant pressure by any suitable means. The metering pumps arefilled by relieving the pressure on the air inlet valves and outletvalves and opening the air bleed valves. The resin and hardener willfill one side of the metering pumps and when illed the outlet valve, airbleed valve and inlet valve are closed. The hydraulic system is filledby opening the air bleed valves and 100 and allowing hydraulic uid toflow into the cylinder from reservoir 88. Air bleed valve is closed whenchamber 28 is filled and valve 90 when the cylinder is filled. Inoperation air cylinder 124 is pressurized actuating lever system '18.Levers 102 will bear against the pistons in the hydraulic ramspressurizing the hydraulic iluid therein. Simultaneous with thepressurizing of the air cylinder, air outlet valves 19 will be opened.The hydraulic pressure of the uid on the diaphragms, being dependent onthe speed and stroke of the piston, will force `a metered amount ofresin and hardener out of the pump forcing a like amount into the mixer.At the end of the air cylinder pumping stroke, the air outlet valve willbe closed and the air inlet valve will be opened allowing thepressurized resin and hardener to act against the diaphragms. Thepressure in the air cylinder will be reversed simultaneously with theopening of the inlet valve moving the levers back slowly so that thediaphragm will be moved to its normal position by the pressure of theresin and hardener.

Although but one embodiment of the present invention has beenillustrated and described, it will be apparent to those skilled in theart that various changes and modiiications may be made therein withoutdeparting from the spirit of the invention or from the scope of theappended claims.

I claim:

1. Fluid metering apparatus comprising a pair of metering pumps eachincluding a cavity having a diaphragm mounted therein and dividing thecavity into two chambers, means for removably mounting the diaphragmswithin the respective pumps, removable pump structures in each pumpproviding an inlet to and yan Outlet from a chamber on one side of therespective diaphragms thereof, means for securing said removable pumpstructures inrplace on the respective pumps in overlying relation tosaiddiaphragm mounting means but independently thereof whereby saidremovable pump structures may be removed from the .pumps withoutdisturbing the diaphragm and its mounting means, mixing means connectedto receive the discharge from lboth of said pumps, lhydraulic actuatingmeans for the pumps including a pair of pistons movable in cylindersconnected respectively to the other of said chambers to force liquidfrom the cylinders into said other chambers respectively, means forsupplying liquid to said cylinders, and means fou simultaneouslyoperating said pistons including motion transmission means connected tosaid pistons and having adjustment means for proportioning the relativelengths of stroke of the pistons within said cylinders thereby 'to forcepredetermined quantities of liquid from said cylinders into said otherchambers of the pumps respec- `tively, and thus displace the respectivepump diaphragms a predetermined amount to actuate the pump diaphragms topump metered quantities of liquids from sources respectively connectedthereto and deliver the same to said mixing means within a predeterminedperiod of time.

2. An apparatus for providing metered quantities of resin and hardenerto a mixer comprising, a source of supply of resin, a source of supplyof hardener, a pair of diaphragm pumps, each including a diaphragm andmeans for mounting the diaphragm Within the pump, pump structures ineach pump deiining with said da phragms `a chamber on each side of saiddiaphragms, means connecting one of said chambers of each of said pumpsto said sources of supply respectively, the pump structures of each pumpwhich deiine the chamber thereof to which said supplies are connectedbeing removably secured to the respective pumps independently of saiddiaphragm mounting means, mixing means connected to receive thedischarge from both of said pumps, hydraulic means including a pair ofpiston type hydraulic rams connected respectively to the other of saidpump chambers for actuating the respective pump diaphragms, motiontransmiszion means interposed between a source of power and said ramsand including adjustable mechanical means for controlling the relativelength of stroke of said ram pistons thereby to displace inpredetermined amounts the respective pump diaphragrns so that the pumpsdeliver metered quantities of resin and hardener to said mixing means,said adjustable means including a pair of pivoted levers having theirfree ends connected to the pistons of the respective rams, and a pair ofcams mounted for linear reciprocal motion and operatively connected tooscillate the levers in both directions of motion, said cams beingadjustable to vary the length of stroke of the pistons of the respectivehydraulic rams. 3. An apparatus for providing metered quantities ofresin and hardener to a mixer comprising, a pair of diaphragm pumps eachincluding means providing a cavity, and a diaphragm mounted in thecavity and providing on opposite sides of the diaphragm a hydraulicsection and a pumping section, removable pump structures providing aninlet to and an Outlet from the pumping section of each pump and meansfor mounting said removable pump structures on the respective pumpsindependently of mounting means for said diaphragms, means forlsupplying dierent iluids to the pumping section of each pump, means forsupplying hydraulic actuating iluid for the hydraulic sections of therespective pumps, mixing means and means for supplying meteredquantities of resin and hardener from said pumps to said mixing means,said last-mentioned means including a pair of piston type hydraulic ramsconnected to the respective -hydraulic sections of said pumps foractuating the pump diaphragms, a lever` system for actuating the pistonsof said rams, said system including a pair of pivoted levers lying in -acommon plane and each having one end connected to a ram piston, a camfollower' carried by each lever, a plate movable in a plane parallel tothe plane of the levers, and a pair of cam plates connected to themovable plate and each including a cam groove for engaging the camfollowers respectively so that movement of the plate will cause thelevers to impart predetermined relative motion to the ram pistons, andmeans for actuating the lever system.

References Cited in the tile of this patent Taber et al. July i4, 19592,895,644

Pande July 2l, 1959 Christensen et al. Aug. 13, 1957

1. FLUID METERING APPARATUS COMPRISING A PAIR OF METERING PUMPS EACHINCLUDING A CAVITY HAVING A DIAPHRAGM MOUNTED THEREIN AND DIVIDING THECAVITY INTO TWO CHAMBERS, MEANS FOR REMOVABLY MOUNTING THE DIAPHRAGMSWITHIN THE RESPECTIVE PUMPS, REMOVABLE PUMP STRUCTURES IN EACH PUMPPROVIDING AN INLET TO AND AN OUTLET FROM A CHAMBER ON ONE SIDE OF THERESPECTIVE DIAPHRAGMS THEREOF, MEANS FOR SECURING SAID REMOVABLE PUMPSTRUCTURES IN PLACE ON THE RESPECTIVE PUMPS IN OVERLYING RELATION TOSAID DIAPHRAGM MOUNTING MEANS BUT INDEPENDENTLY THEREOF WHEREBY SAIDREMOVABLE PUMP STRUCTURES MAY BE REMOVED FROM THE PUMPS WITHOUTDISTURBING THE DIAPHRAGM AND ITS MOUNTING MEANS, MIXING MEANS CONNECTEDTO RECEIVE THE DISCHARGE FROM BOTH OF SAID PUMPS, HYDRAULIC ACTUATINGMEANS FOR THE PUMPS INCLUDING A PAIR OF PISTONS MOVABLE IN CYLINDERSCONNECTED RESPECTIVELY TO THE OTHER OF SAID CHAMBERS TO FORCE LIQUIDFROM THE CYLINDERS INTO SAID OTHER CHAMBERS RESPECTIVELY, MEANS FORSUPPLYING LIQUID TO SAID CYLINDERS, AND MEANS FOR SIMULTANEOUSLYOPERATING SAID PISTONS INCLUDING MOTION TRANSMISSION MEANS CONNECTED TOSAID PISTONS AND HAVING ADJUSTMENT MEANS FOR PROPORTIONING THE RELATIVELENGTHS OF STROKE OF THE PISTONS WITHIN SAID CYLINDERS THEREBY TO FORCEPREDETERMINED QUANTITIES OF LIQUID FROM SAID CYLINDERS INTO SAID OTHERCHAMBERS OF THE PUMP DIAPHRAGMS TIVELY, AND THUS DISPLACE THE RESPECTIVEPUMP DIAPHRAGMS A PREDETERMINED AMOUNT TO ACTUATE THE PUMP DIAPHRAGMS TOPUMP METERED QUANTITIES OF LIQUIDS FROM SOURCES RESPECTIVELY CONNECTEDTHERETO AND DELIVER THE SAME TO SAID MIXING MEANS WITHIN A PREDTERMINEDPERIOD OF TIME.